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991.
992.
993.
A phase III multicenter study was conducted in 89 patients with known intracranial vascular lesions to evaluate an extracellular gadolinium contrast agent, gadoteridol, for intracranial magnetic resonance (MR) angiography. The pre- and postcontrast MR angiograms of 82 patients were evaluated by the unblinded investigators and by two blinded readers (A and B) for visualization of lesions; arterial and venous anatomy; extent, size, and number of lesions; and disease classification. The unblinded readers indicated that lesions were visualized better on postcontrast images in the following categories: venous anatomy, 87 (81%) of 107 lesions; arterial anatomy, 43 lesions (40%); and extent or size of lesions, 38 lesions (36%). In 29 (35%) of 82 patients, the unblinded readers determined that enhanced MR angiography provided more diagnostic information than unenhanced MR angiography. The blinded readers determined that enhanced MR angiography provided more information for visualization of vascular anatomy in more than 60% of cases. The additional information provided with gadoteridol would have changed the diagnosis in nine (8%) of 107 lesions seen by the unblinded readers, 11 (12%) of 90 lesions seen by reader A, and three (3%) of 93 lesions seen by reader B. The results confirm that the use of gadoteridol improves the visualization of intracranial vascular lesions with MR angiography. The authors conclude that development of new postprocessing algorithms will improve the utility of contrast-enhanced MR angiography.  相似文献   
994.
Cholesterol intakes in Britain have been re-estimated by analysing Total Diet samples taken in 1991 and from 1993 National Food Survey records. The Total Diet samples contained only 284 mg/day compared with 319 mg/day in 1987 and 337 mg/day in 1981, while the National Food Survey showed intakes had fallen to 238 mg/day from 259 mg/day in 1990 and 405 mg/day in 1970-75. More details of the intakes by adults in 1986/87 are given, and compared with the results from the other methods. Daily intakes of eight phytosterols were also estimated, the main ones being β-sitosterol, campesterol, stigmasterol and 57-stigmastenol whose intakes were 104, 49, 10 and 4 mg/day, respectively, in 1991. These intakes had increased since 1981, reflecting the rising consumption of vegetable oils.  相似文献   
995.
We describe the pattern and progression of atrophy delineated using fluid registration of serial magnetic resonance imaging scans in a case of multiple system atrophy (MSA). The in vivo findings were consistent with those found at postmortem, including significant supratentorial atrophy concurrent with an unusual degree of cognitive impairment for MSA.  相似文献   
996.
Summary Phosphonacetyl-l-aspartate (PALA), an inhibitor of aspartate transcarbamylase that depletes uridine nucleotide pools, selectively potentiates the antitumor activity of 5-fluorouracil (5-FU) in preclinical models. Due to the promising results we obtained using PALA/5-FU in colorectal cancer, we performed a phase II trial in patients presenting with advanced pancreatic cancer. PALA was given intravenously at 250 mg/m2 on day 1, followed 24 h later by 2,600 mg/m2 5-FU given by 24-h infusion. Treatments were repeated weekly. A total of 41 patients who had not previously undergone chemotherapy were entered in the trial; of these, 35 were evaluable for response. Toxicity was generally mild to moderate; neurotoxicity (13/35) and diarrhea (8/35) predominated. Among the 35 patients, 1 achieved a complete response and 4, a partial remission, for an overall response rate of 14%. The median survival was 5.1 months. Pretreatment with PALA alone was not sufficient to enhance the activity of 5-FU in pancreatic cancer.Supported in part by grant CA 06927 from the National Cancer Institute  相似文献   
997.
Objective To assess the relation between perineal inspection and sphincter integrity in parous women.
Design Prospective observational study.
Setting District general hospital.
Population Fifty-seven consecutive parous women attending a gynaecology clinic for problems unrelated to the pelvic floor.
Methods A detailed history of bowel function and mode of delivery obtained; the perineum inspected to determine the presence and position of scarring, and anal endosonography performed.
Results In 19 women with an intact perineum on inspection, endosonography showed perineal scarring in five, with both perineal and sphincter scarring in three. Four had urge faecal incontinence. Three patients had a perineal tear only on inspection, but this group was too small for analysis and was discounted. Nine had an episiotomy scar only. Endosonography demonstrated perineal scarring in four, and combined perineal and sphincter scarring in two; one woman in this group had urge faecal incontinence. Twenty-six women had episiotomy and perineal tears on inspection. Endosonography revealed underlying perineal scarring in five women, with combined perineal and sphincter scarring in 14; six women in this group had urge faecal incontinence and one passive incontinence for flatus. Sonographically the scarring was anterior and circumferential rather than radial, and mostly left-sided, whereas on inspection episiotomy and perineal scarring were right sided.
Conclusions A normal perineum on clinical examination does not exclude underlying sphincter damage. The incidence of sphincter damage increases significantly when an episiotomy scar is associated with a perineal tear.  相似文献   
998.
Purpose. The effect of retrograde cerebral perfusion on the incidence of stroke and death among patients undergoing repair of aneurysms of the ascending aorta and transverse arch was determined.

Material and Methods. Between January 1991 and March 1995, 161 patients were operated on for aneurysms of the ascending aorta and transverse arch. Thirty-three of the patients (20%) had an aneurysm of the ascending aorta only and 128 (80%) had aneurysms of both the ascending aorta and the transverse arch. All the patients underwent cardiopulmonary bypass, profound hypothermia, and circulatory arrest, and 120 (74%) also underwent retrograde cerebral perfusion. Median pump time was 143 minutes (range, 21 to 461 minutes). Median circulatory arrest time was 42 minutes (range, 8 to 111 minutes), and median myocardial ischemic time was 71 minutes (range, 14 to 306 minutes).

Results. The overall 30-day mortality rate was 6% (9 patients) and the incidence of stroke was 4% (7 patients). The use of retrograde cerebral perfusion demonstrated a protective effect against stroke (3 of 120 patients, or 3%) compared with no retrograde cerebral perfusion (4 of 41 patients, or 9%; odds ratio, 0.24; confidence interval, 0.06 to 0.99; p < 0.049). This was most significant in patients more than 70 years of age; none of the 36 elderly patients who received retrograde cerebral perfusion had a stroke, compared with 3 of the 13 (23%) who did not (p < 0.003). Only pump time was associated with an increased risk of stroke (odds ratio, 1.01; 95% confidence interval, 1.00 to 1.02; p < 0.005). Pump time also was associated with increased mortality (odds ratio, 1.01; 95% confidence interval, 1.00 to 1.02; p < 0.008).

Conclusion. Retrograde cerebral perfusion decreased the incidence of stroke in patients undergoing repair of aneurysms of the ascending aorta and transverse arch.  相似文献   

999.
The purpose of this paper is to provide an historical review of the progression of events within the jurisdiction of the province of Ontario related to the issue of laboratory diagnosis and the profession of chiropractic. The provisions of relevant legislation, task forces, Councils, reviews, consensus statements, Commissions and committees, are highlighted and discussed during respective time periods. Chiropractors had entitlement to order and perform laboratory tests until 1972 when a regulatory amendment, made without consultation with the chiropractic profession, precluded their continuing entitlement. Chiropractic patients require access to diagnostic laboratory services and equitable access to necessary laboratory services should be restored and preserved. This is consistent with the academic institutional accreditation standards of chiropractic education and the jurisdictional regulatory mechanisms of chiropractic practice and is consistent with both protecting and enhancing the public interest.  相似文献   
1000.
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